Mashiro Ichijo is a girls' idol, handsome and kind, but he has been hiding a secret all his life: he's not truly male, nor entirely female. He has the upper body of a male but the lower body of a female. When a mysterious school nurse introduces him to a new class, he finds that in order to graduate he has to go to a world of dreams to find a mysterious key, competing with other classmates to find it. As he struggles with his gender identity, he tries to decide whether he wants to live as a male and go out with one of the prettiest girls in school or as a female and be with the cute male slacker, both of which are madly in love with Ichijo.
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